CN211779127U

CN211779127U - Pneumatic diaphragm valve

Info

Publication number: CN211779127U
Application number: CN202020277641.2U
Authority: CN
Inventors: 张福军
Original assignee: Beijing Haiying Ruifeng Technology Co ltd
Current assignee: Beijing Haiying Ruifeng Technology Co ltd
Priority date: 2020-03-09
Filing date: 2020-03-09
Publication date: 2020-10-27
Anticipated expiration: 2030-03-09

Abstract

The utility model relates to the technical field of biological fermentation industrial production, and provides a pneumatic diaphragm valve, which comprises a cylinder body and a piston, wherein the cylinder body comprises a cylinder base, a cylinder, a gland and an elastic part; the gland is arranged on one side of the cylinder, which is far away from the cylinder base, and the part of the gland is positioned on the outer side of the cylinder; one end of the elastic piece is abutted against the piston, and the other end of the piston is abutted against the gland so as to press the gland on the cylinder; the gland is movably arranged relative to the cylinder, so that after the gland is separated from the cylinder, the cylinder is movably arranged relative to the cylinder base. The pneumatic diaphragm valve of this disclosure is through being split cylinder body into cylinder base, cylinder and gland to the assembly and the maintenance degree of difficulty of pneumatic diaphragm valve have been reduced.

Description

Pneumatic diaphragm valve

Technical Field

The disclosure relates to the technical field of biological fermentation industrial production, in particular to a pneumatic diaphragm valve.

Background

The pneumatic diaphragm valve has the characteristics of smooth internal structure, no dead angle and easy sterilization, is very important valve equipment in biological fermentation production, and is adopted by all sterile pipelines produced by biological fermentation. At present, the pneumatic diaphragm valve used in the production process of the biological fermentation industry adopts an integrated cylinder as an actuator, the difficulty of assembly and maintenance is very high, the valve must be taken to a table bed for operation, sometimes, the valve even needs to be sent back to a diaphragm valve manufacturer, the maintenance time is long, and the production is influenced.

SUMMERY OF THE UTILITY MODEL

It is a primary object of the present disclosure to overcome at least one of the above-mentioned deficiencies of the prior art and to provide a pneumatic diaphragm valve.

The utility model provides a pneumatic diaphragm valve, including cylinder body and piston, the cylinder body includes:

a cylinder base;

the cylinder is detachably connected with the cylinder base, and the piston is arranged in the cylinder;

the gland is arranged on one side of the cylinder, which is far away from the cylinder base, and the part of the gland is positioned on the outer side of the cylinder;

one end of the elastic piece is abutted with the piston, and the other end of the piston is abutted with the gland so as to press the gland on the cylinder;

the gland is movably arranged relative to the cylinder, so that after the gland is separated from the cylinder, the cylinder is movably arranged relative to the cylinder base.

In an embodiment of the present invention, the cylinder is connected to the cylinder base by a screw, and the pneumatic diaphragm valve further includes:

and the cylinder sealing ring is arranged between the cylinder and the cylinder base.

In an embodiment of the present invention, the pneumatic diaphragm valve further comprises:

a valve body;

the diaphragm is arranged on the valve body, and the cylinder base is arranged on one side of the diaphragm, which is far away from the valve body;

the diaphragm is connected to the one end of valve rod, and the valve rod is connected with the piston after passing the cylinder base.

one end of the stroke converter is connected with the diaphragm, and the other end of the stroke converter, which is far away from the diaphragm, is arranged in the valve rod;

wherein the stroke converter is movably arranged in the axial direction of the valve rod.

In an embodiment of the present invention, the stroke converter is provided with a radial through hole, and the pneumatic diaphragm valve further includes:

and the connecting pin is arranged on the valve rod, the connecting pin is inserted in the radial through hole, and the stroke converter is movably arranged relative to the connecting pin along the axial direction of the valve rod.

In an embodiment of the present invention, the connecting pin is inserted in the radial direction of the valve rod, and both ends of the connecting pin are located outside the valve rod, and along the moving direction of the stroke converter, the size of the connecting pin is smaller than that of the radial through hole, so that the stroke converter is movably disposed relative to the connecting pin.

In an embodiment of the present invention, the diaphragm valve further includes:

the valve core is arranged on one side of the diaphragm, which is far away from the valve body, and the valve core is clamped between the diaphragm and the valve rod;

the stroke converter is connected with the diaphragm through the first fastener.

the valve rod is sleeved with the two flat gaskets in pair, and the piston is clamped between the two flat gaskets in pair;

a valve stem nut connected to the valve stem and contacting a flat gasket to secure the piston to the valve stem;

and the valve rod sealing ring is sleeved on the valve rod and is contacted with the other flat gasket, so that the valve rod sealing ring is clamped between the piston and the flat gasket.

the bearing is arranged on the cylinder base, and the valve rod is arranged in the bearing in a penetrating manner;

the cylinder seat sealing ring is arranged in the cylinder base and is abutted against one end of the bearing;

and the shaft seal is arranged in the cylinder base and is in contact with the cylinder base sealing ring so as to clamp the cylinder base sealing ring between the bearing and the shaft seal.

In an embodiment of the utility model, one side that the piston is close to the gland is provided with the mounting groove, and the one end setting of elastic component is in the mounting groove, and pneumatic diaphragm valve still includes:

the double-acting cylinder sealing ring is sleeved on the piston and clamped between the piston and the cylinder.

The utility model discloses a pneumatic diaphragm valve is through being cylinder base, cylinder and gland with the cylinder body split to the assembly and the maintenance degree of difficulty of pneumatic diaphragm valve have been reduced.

Drawings

Various objects, features and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments thereof, when considered in conjunction with the accompanying drawings. The drawings are merely exemplary illustrations of the disclosure and are not necessarily drawn to scale. In the drawings, like reference characters designate the same or similar parts throughout the different views. Wherein:

FIG. 1 is a schematic diagram illustrating the construction of a pneumatic diaphragm valve according to an exemplary embodiment;

FIG. 2 is a schematic diagram illustrating a first connection state of a stroke converter and a valve stem according to an exemplary embodiment;

FIG. 3 is a schematic diagram illustrating a second connection state of a stroke converter and a valve stem according to an exemplary embodiment;

FIG. 4 is a schematic diagram illustrating the structure of a specialized tool according to an exemplary embodiment.

The reference numerals are explained below:

10. a valve body; 11. a second fastener; 20. a membrane; 30. a cylinder body; 31. a cylinder base; 32. a cylinder; 33. a gland; 34. a cylinder seal ring; 40. a valve core; 50. a stroke converter; 51. a radial through hole; 52. a first fastener; 60. a valve stem; 61. a connecting pin; 62. a bearing; 63. a cylinder seat seal ring; 64. shaft sealing; 70. a piston; 71. a double-acting cylinder seal ring; 72. flattening the cushion; 73. a valve stem nut; 74. a valve stem seal ring; 75. mounting grooves; 76. an elastic member; 80. an indication lever; 90. fixing the screw rod; 91. the handle is rotated.

Detailed Description

Exemplary embodiments that embody features and advantages of the present disclosure are described in detail below in the specification. It is to be understood that the disclosure is capable of various modifications in various embodiments without departing from the scope of the disclosure, and that the description and drawings are to be regarded as illustrative in nature, and not as restrictive.

In the following description of various exemplary embodiments of the disclosure, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various exemplary structures, systems, and steps in which aspects of the disclosure may be practiced. It is to be understood that other specific arrangements of parts, structures, example devices, systems, and steps may be utilized and structural and functional modifications may be made without departing from the scope of the present disclosure. Moreover, although the terms "over," "between," "within," and the like may be used in this specification to describe various example features and elements of the disclosure, these terms are used herein for convenience only, e.g., in accordance with the orientation of the examples in the figures. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures in order to fall within the scope of this disclosure.

An embodiment of the present invention provides a pneumatic diaphragm valve, please refer to fig. 1 to 3, the pneumatic diaphragm valve includes a cylinder body 30 and a piston 70, the cylinder body 30 includes: a cylinder base 31; the air cylinder 32, the air cylinder 32 is detachably connected with the air cylinder base 31, and the piston 70 is arranged in the air cylinder 32; the gland 33, the gland 33 is set up in the cylinder 32 and far away from one side of the cylinder base 31, the part of the gland 33 locates at the outside of the cylinder 32; an elastic member 76, one end of the elastic member 76 is abutted against the piston 70, and the other end of the piston 70 is abutted against the gland 33, so as to press the gland 33 on the cylinder 32; wherein the gland 33 is movably disposed with respect to the cylinder 32, so that the cylinder 32 is movably disposed with respect to the cylinder base 31 after the gland 33 is separated from the cylinder 32.

The utility model discloses a pneumatic diaphragm valve of an embodiment is through being cylinder base 31, cylinder 32 and gland 33 with cylinder body 30 split, and cylinder body 30 comprises the structure of a plurality of splittable promptly to the assembly and the maintenance degree of difficulty of pneumatic diaphragm valve have been reduced.

In one embodiment, the cylinder body 30 has an inner cavity, that is, the cylinder base 31, the cylinder 32 and the gland 33 enclose an inner cavity, the piston 70 and the elastic member 76 are located in the inner cavity, a portion of the gland 33 is located in the inner cavity, and the gland 33 and the piston 70 press the elastic member 76 to press the gland 33 against the cylinder 32 under the action of the elastic member 76, that is, after the cylinder base 31 and the cylinder 32 are connected, the gland 33 abuts against the inner side of the cylinder 32 under the action of the elastic member 76.

In one embodiment, as shown in fig. 1, the cylinder 32 is threadedly connected to the cylinder base 31, and the pneumatic diaphragm valve further comprises: and the cylinder sealing ring 34 is arranged between the cylinder 32 and the cylinder base 31. The cylinder 32 and the cylinder base 31 are connected through threads, so that assembly is convenient, connection stability is good, and the sealing performance between the cylinder 32 and the cylinder base 31 is improved due to the arrangement of the cylinder sealing ring 34.

In one embodiment, as shown in fig. 1, the pneumatic diaphragm valve further comprises: a valve body 10; the diaphragm 20, the diaphragm 20 is arranged on the valve body 10, and the cylinder base 31 is arranged on one side of the diaphragm 20 far away from the valve body 10; and a valve stem 60, wherein one end of the valve stem 60 is connected with the diaphragm 20, and the valve stem 60 is connected with the piston 70 after penetrating through the cylinder base 31. In particular use, movement of the piston 70 causes the valve stem 60 to actuate movement of the diaphragm 20 relative to the valve body 10.

In one embodiment, the valve body 10, the diaphragm 20 and the cylinder base 31 are fixedly connected by a plurality of second fastening members 11, and the diaphragm 20 is sandwiched between the valve body 10 and the cylinder base 31.

In one embodiment, as shown in fig. 1, the pneumatic diaphragm valve further comprises: a stroke converter 50, one end of the stroke converter 50 is connected with the diaphragm 20, and the other end of the stroke converter 50 far away from the diaphragm 20 is arranged in the valve rod 60; wherein the stroke converter 50 is movably arranged in the axial direction of the valve stem 60. The stroke converter 50 is arranged to enable the valve rod 60 to be non-rigidly connected with the diaphragm 20, that is, in a specific use, the valve rod 60 is movably arranged relative to the diaphragm 20, so that the diaphragm 20 is uniformly stressed, the sealing performance of the pneumatic diaphragm valve is improved, and the service life of the diaphragm 20 is prolonged.

In one embodiment, as shown in fig. 2 and 3, the stroke converter 50 is provided with a radial through hole 51, and the pneumatic diaphragm valve further includes: and a connecting pin 61, the connecting pin 61 being provided on the valve stem 60, the connecting pin 61 being inserted in the radial through hole 51, the stroke converter 50 being movably provided relative to the connecting pin 61 in the axial direction of the valve stem 60. The connecting pin 61 serves to prevent the stroke converter 50 from being disengaged from the stem 60 and to ensure that the diaphragm 20 moves relative to the stem 60.

In one embodiment, as shown in fig. 2 and 3, the connecting pin 61 is inserted in the radial direction of the valve stem 60, and both ends of the connecting pin 61 are located outside the valve stem 60, and the size of the connecting pin 61 is smaller than that of the radial through hole 51 in the moving direction of the stroke converter 50, so that the stroke converter 50 is movably disposed with respect to the connecting pin 61. The depth dimension of the radial through hole 51 is larger than the width dimension of the connecting pin 61 in the moving direction of the stroke converter 50, that is, in the axial direction of the stroke converter 50 (the projection of the connecting pin 61 on a certain plane has a length dimension and a width dimension, and the length dimension thereof extends in the axial direction of the radial through hole 51), so that it can be ensured that the stroke converter 50 is movable relative to the connecting pin 61, as in the state of fig. 2 to 3, the stroke converter 50 moves to the inside of the valve stem 60 by a certain dimension.

In one embodiment, as shown in fig. 1, the pneumatic diaphragm valve further comprises: the valve core 40 is arranged on one side of the diaphragm 20 far away from the valve body 10, and the valve core 40 is clamped between the diaphragm 20 and the valve rod 60; the first fastener 52, the stroke converter 50 and the diaphragm 20 are connected by the first fastener 52. The first fastening member 52 is a screw or a bolt, and the like, and the stroke converter 50 is fixedly connected to the diaphragm 20, that is, the stroke converter 50 is connected to the diaphragm 20 through the first fastening member 52. Wherein the valve core 40 is disposed in the cylinder base 31.

In one embodiment, as shown in fig. 1, the pneumatic diaphragm valve further comprises: the flat gaskets 72 are arranged in pairs, the two paired flat gaskets 72 are sleeved on the valve rod 60, and the piston 70 is clamped between the two paired flat gaskets 72; a stem nut 73, the stem nut 73 being attached to the stem 60 and contacting a flat pad 72 to fix the piston 70 to the stem 60; and the valve rod sealing ring 74 is sleeved on the valve rod 60 and is in contact with the other flat gasket 72, so that the valve rod sealing ring 74 is clamped between the piston 70 and the flat gasket 72. The stem nut 73 presses the pair of two flat washers 72 and the piston 70 against the valve stem 60.

In one embodiment, the pneumatic diaphragm valve further comprises: the bearing 62 is arranged on the cylinder base 31, and the valve rod 60 penetrates through the bearing 62; the cylinder seat sealing ring 63 is arranged in the cylinder base 31, and the cylinder seat sealing ring 63 is abutted with one end of the bearing 62; the shaft seal 64 is disposed in the cylinder base 31, and the shaft seal 64 is in contact with the cylinder block seal 63, so that the cylinder block seal 63 is interposed between the bearing 62 and the shaft seal 64. The bearing 62, the cylinder block seal 63, and the shaft seal 64 are all disposed within the cylinder block 31.

In one embodiment, a side of the piston 70 close to the gland 33 is provided with a mounting groove 75, one end of the elastic member 76 is disposed in the mounting groove 75, and the pneumatic diaphragm valve further includes: the double-acting cylinder sealing ring 71 is sleeved on the piston 70, and the double-acting cylinder sealing ring 71 is clamped between the piston 70 and the cylinder 32. The mounting groove 75 is an annular groove, the elastic member 76 is a spring, and one end of the spring is disposed in the annular groove.

In one embodiment, for the installation of the cylinder body 30, when the cylinder 32 is assembled, the gland 33 is flatly covered on the elastic member 76, the cylinder 32 is sleeved, the fixing screw 90 of the special tool is inserted into the central hole of the gland 33, the fixing screw is sleeved on the top end of the valve rod 60 and is screwed, and the rotating handle 91 of the special tool is rotated to be tightly attached to the top of the gland 33. The rotating handle 91 of the special tool is slowly rotated to make the gland 33 move downwards to compress the elastic element 76, at the moment, the air cylinder 32 also moves downwards, the air cylinder 32 is connected with the air cylinder base 31 by adopting a screw thread, the air cylinder 32 is rotated by hands to tighten the screw thread, if the air cylinder 32 is not completely meshed with the air cylinder base 31 when the top of the air cylinder 32 is tightly pressed with the gland 33, the rotating handle 91 of the special tool is rotated again to further compress the elastic element 76, so that the air cylinder 32 can be rotated by hands again. This is repeated until the cylinder 32 is fully assembled. The structure of the special tool is shown in fig. 4, the special tool comprises a rotary handle 91 and a fixed screw 90, and the rotary handle 91 can rotate along the fixed screw 90 to move up and down.

In one embodiment, for the removal of the cylinder body 30, the indication rod 80 of the pneumatic diaphragm valve is removed, the fixing screw 90 of the special tool is inserted into the central hole of the gland 33 and fastened with the valve rod 60, the rotating handle 91 of the special tool is rotated to press down the gland 33, the elastic member 76 is compressed to separate the top of the cylinder 32 from the gland 33, at this time, the cylinder 32 can be unscrewed by hand, the cylinder 32 is unscrewed, the top of the cylinder 32 is lifted until the top of the cylinder 32 is attached to the lower part of the rotating handle 91 of the special tool, at this time, the rotating handle 91 of the special tool is rotated to lift the rotating handle 91, the elastic member 76 extends to slowly lift, and the loosening of the rotating handle 91 is stopped when the upper surface of the gland 33 is about to contact with the top. At this time, the cylinder 32 has a certain unscrewing distance, the cylinder 32 is unscrewed by hand until the cylinder 32 is completely separated from the cylinder base 31, the stress of the elastic piece 76 is completely released, the special tool is taken down, and the cylinder 32 is detached.

The utility model discloses a novel pneumatic diaphragm valve that pneumatic diaphragm valve of an embodiment is, including valve body 10, diaphragm 20 is installed to the upper end of valve body 10, diaphragm 20 top installation cylinder base 31, valve body 10, diaphragm 20 and cylinder base 31 pass through the bolt (second fastener 11) to be fixed together, cylinder base 31's center department is equipped with a mounting hole, the inside bearing 62 that installs of mounting hole, the lower extreme of valve rod 60 passes bearing 62 and extends to the lower part of cylinder base 31, the lower extreme of valve rod 60 is with pin (connecting pin 61) connection stroke converter 50, stroke converter 50 passes through screw (first fastener 52) and connects diaphragm 20, be fixed with a case 40 between diaphragm 20 and the valve rod 60, the screw passes the hole of case 40 and is connected with valve rod 60, an upper end internally mounted piston 70 of cylinder base 31, piston 70 installs a double-acting cylinder sealing washer 71, piston 70 is equipped with a centre bore, the upper end of the valve rod 60 penetrates through the central hole and then fixes the valve rod 60 and the piston 70 through a nut (a valve rod nut 73), the upper surface of the piston 70 is provided with an annular groove (an installation groove 75), a spring (an elastic piece 76) is installed on the annular groove, a spring gland (a gland 33) is installed at the top end of the spring, the cylinder base 31 is in threaded connection with a cylinder 32, the top of the cylinder 32 is sleeved on the spring gland, the center of the spring gland is provided with an indication rod 80, and the lower end of the indication rod 80 is connected with the. The cylinder base 31 is provided with a cylinder base sealing ring 63 with an annular structure at the upper end of the bearing 62, and a shaft seal 64 is arranged at the upper end of the cylinder base sealing ring 63, so that the sealing performance between the bearing 62 and the cylinder base 31 is improved. An air cylinder sealing ring 34 is arranged in a gap between the air cylinder base 31 and the air cylinder 32, the sealing performance between the air cylinder base 31 and the air cylinder 32 is improved, flat gaskets 72 are arranged at the upper end and the lower end of the valve rod 60, which are positioned on the piston 70, a valve rod sealing ring 74 is also arranged between the piston 70 and the valve rod 60, and a valve rod nut 73 pressing the flat gaskets 72 is in threaded connection above the flat gasket 72 at the upper end of the valve rod 60. The top of cylinder 32 is equipped with a central round hole, and cylinder 32 is passed to spring gland upper portion ring, and the upper surface of spring gland and the laminating of the top of cylinder 32, spring gland can move about from top to bottom in the axial, and the lower surface of spring gland is supported to the spring upper end, and the ring channel of piston 70 is supported to the spring lower extreme.

The utility model discloses a pneumatic diaphragm valve simple structure, greatly reduced the assembly degree of difficulty of valve, through adopting the design of spring gland, compression spring in advance, with the original power at loading cylinder top of spring, the conversion loading is on the gland, there is not external load between cylinder and the support, just can easily rotating cylinder, assembly, maintenance personal only need manually just can accomplish the operation, make the assembly degree of difficulty greatly reduced of cylinder, the assembly efficiency of valve has been improved, the maintenance time of equipment shortens, thereby the fortune dimension cost of biological fermentation production has been reduced.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and exemplary embodiments be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A pneumatic diaphragm valve comprising a cylinder body (30) and a piston (70), wherein the cylinder body (30) comprises:

a cylinder base (31);

the air cylinder (32), the air cylinder (32) is detachably connected with the air cylinder base (31), and the piston (70) is arranged in the air cylinder (32);

the gland (33), the gland (33) is set up in the cylinder (32) far away from one side of the cylinder base (31), the part of the gland (33) lies in the outside of the cylinder (32);

one end of the elastic piece (76) is abutted with the piston (70), and the other end of the piston (70) is abutted with the gland (33) so as to press the gland (33) on the cylinder (32);

wherein the gland (33) is movably arranged relative to the cylinder (32) such that the cylinder (32) is movably arranged relative to the cylinder base (31) after the gland (33) is separated from the cylinder (32).

2. The pneumatic diaphragm valve of claim 1, wherein the cylinder (32) is threaded with the cylinder base (31), the pneumatic diaphragm valve further comprising:

the air cylinder sealing ring (34) is arranged between the air cylinder (32) and the air cylinder base (31).

3. The pneumatic diaphragm valve of claim 1, further comprising:

a valve body (10);

the diaphragm (20) is arranged on the valve body (10), and the cylinder base (31) is arranged on one side, far away from the valve body (10), of the diaphragm (20);

the diaphragm (20) is connected to one end of the valve rod (60), and the valve rod (60) penetrates through the cylinder base (31) and then is connected with the piston (70).

4. The pneumatic diaphragm valve of claim 3 further comprising:

a stroke converter (50), wherein one end of the stroke converter (50) is connected with the diaphragm (20), and the other end of the stroke converter (50) far away from the diaphragm (20) is arranged in the valve rod (60);

wherein the stroke converter (50) is movably disposed in an axial direction of the valve stem (60).

5. A pneumatic diaphragm valve according to claim 4 where the stroke converter (50) is provided with a radial through hole (51), the valve further comprising:

a connecting pin (61), the connecting pin (61) being provided on the valve stem (60), the connecting pin (61) being inserted in the radial through hole (51), the stroke converter (50) being movably provided with respect to the connecting pin (61) in an axial direction of the valve stem (60).

6. The pneumatic diaphragm valve according to claim 5, wherein the connecting pin (61) is inserted in a radial direction of the valve rod (60) with both ends of the connecting pin (61) located outside the valve rod (60), and a size of the connecting pin (61) is smaller than a size of the radial through hole (51) in a moving direction of the stroke converter (50) so that the stroke converter (50) is movably disposed with respect to the connecting pin (61).

7. The pneumatic diaphragm valve of any of claims 4 to 6 further comprising:

the valve core (40), the valve core (40) is arranged on one side of the diaphragm (20) far away from the valve body (10), and the valve core (40) is clamped between the diaphragm (20) and the valve rod (60);

a first fastener (52), the stroke converter (50) and the diaphragm (20) being connected by the first fastener (52).

8. The pneumatic diaphragm valve of claim 3 further comprising:

the flat gaskets (72) are arranged in pairs, the two flat gaskets (72) in a pair are sleeved on the valve rod (60), and the piston (70) is clamped between the two flat gaskets (72) in a pair;

a stem nut (73), said stem nut (73) attached to said valve stem (60) and contacting one of said flat pads (72) to secure said piston (70) to said valve stem (60);

and the valve rod sealing ring (74) is sleeved on the valve rod (60) and is in contact with the other flat gasket (72), so that the valve rod sealing ring (74) is clamped between the piston (70) and the flat gasket (72).

9. The pneumatic diaphragm valve of claim 3 further comprising:

the bearing (62), the said bearing (62) is set up on the said cylinder base (31), the said valve stem (60) is worn and set up in the said bearing (62);

the cylinder seat sealing ring (63) is arranged in the cylinder base (31) and is abutted against one end of the bearing (62);

the shaft seal (64) is arranged in the cylinder base (31) and is in contact with the cylinder base sealing ring (63), so that the cylinder base sealing ring (63) is clamped between the bearing (62) and the shaft seal (64).

10. The pneumatic diaphragm valve of claim 1, wherein a side of the piston (70) adjacent to the gland (33) is provided with a mounting groove (75), one end of the elastic member (76) is disposed in the mounting groove (75), the pneumatic diaphragm valve further comprising:

double-acting cylinder sealing washer (71), double-acting cylinder sealing washer (71) cover is established piston (70) are last, double-acting cylinder sealing washer (71) press from both sides and establish piston (70) with between cylinder (32).